A diatomic molecule, among the following species, that only has $\mathrm{\pi }$ bonds according to the Molecular Orbital Theory (MOT) is:

1.	Be2	2.	O2
3.	N2	4.	C2

Among the following, which has the maximum hydration energy?

1. OH^-

2. ${\mathrm{NH}}_4^{+}$

3. F^-

4. H⁺

Among the following oxides, which has the maximum lattice energy?
1. MgO
2. CaO
3. SrO
4. BaO

Which of the following pairs of species have similar shapes?

The number of unpaired electrons in a paramagnetic diatomic molecule of an element with atomic number 16 is:

1. 2

2. 3

3. 4

4. 1

Which of the following is the most basic oxide?

1. $A{l}_2{O}_3$

2. $S{b}_2{O}_3$

3. $B{i}_2{O}_3$

4. $Se{O}_2$

In which of the following pairs, the two species are iso-structural?

1. $S{F}_4 and Xe{F}_4$

2. $S{O}_3^{2-} and N{O}_3^{-}$

3. $B{F}_3 and N{F}_3$

4. $Br{O}_3^{-} and Xe{O}_3$

The correct order of C-O bond length among CO, ${\mathrm{CO}}_3^{2-}$ , CO₂ is:

1. $C{O}_2<C{O}_3^{2-}<CO$

2. $CO<C{O}_3^{2-}<C{O}_2$

3. $C{O}_3^{2-}<C{O}_2<CO$

4. $CO<C{O}_2<C{O}_3^{2-}$

The correct order of increasing bond order among the given is:

1. ${\mathrm{O}}_2^{-}$ $<$ $\mathrm{NO}$ $<$ ${\mathrm{C}}_2^{2-}$ $<$ ${\mathrm{He}}_2^{+}$

2. $\mathrm{NO}$ $<$ ${\mathrm{C}}_2^{2-}$ $<$ ${\mathrm{O}}_2^{-}$ $<$ ${\mathrm{He}}_2^{+}$

3. ${\mathrm{C}}_2^{2-}$ $<$ ${\mathrm{He}}_2^{+}$ $<$ $\mathrm{NO}$ $<$ ${\mathrm{O}}_2^{-}$

4. ${\mathrm{He}}_2^{+}$ $<$ ${\mathrm{O}}_2^{-}$ $<$ $\mathrm{NO}$ $<$ ${\mathrm{C}}_2^{2-}$

The correct state of hybridisation of C₂, C₃, C₅ and C₆ of the hydrocarbon 

 is in the sequence:
1. sp, sp³, sp² and sp³
2. sp³, sp², sp² and sp
3. sp, sp², sp² and sp³
4. sp, sp², sp³ and sp²